Concrete mixer



April 20 1926. 1,581,492 A. w. RYBECK CONCRETE MIXER Filed April 1e, 1923 2 sheets-sheet 1 April 2o, 1926. 1,581,492

A. W. RYBECK CONCRETE MIXER Filed Apr'il 16 1923 2 Sheets-Sheet 2 I QE J0 am vPatented Apr. 20, 1926.

UNITED STATES lPATENT OFFICE.

ADOLPH W. RYBECK, F MILWAUKEE, WISCONSIN, ASSIGNOR TO THE T. L. SMITH COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

CONCRETE MIXER.

Application tiled April 16, 1923. Serial No. 632,301.

ing at Milwaukee, waukee and State of 1'V1seonsin, have 1n- ,vented cert-ain new and useful Improvements in Concrete Mixers, of which the following is a specification.

This invention relates to a new and improved concrete mixer and more specifically to a portable mixer of the tilting type.

As is well known in the art, certain types of concrete mixers are constructed with the mixing drum carried upon a cradle which is hung in trunnions and which may be swung upon the trunnions to tilt the mixing drum for the purpose of discharging the concrete mixed therein.

This form of construction has the a-dvanl tage of ati'ording a very rapid and efficient discharge, but hereto-fore has been too heavy a construction for general use in relatively small portable machines of types loading and discharging through separate, oppositely placed openings in It is an object of the present invention to provide a portable mixer of the tilting type in which the drum is both supported and guided from the cradle by means of rollers interfitting with a circumferential recess formed in the member'encirc'ling the drum.

It is an additional object to provide a construct-ion of this character in which the cradle may be an integral casting provided with extensions adapted to carry the drum support and guide rollers.

It is also an object to provide a portable mixer of the tilting type which is composed of but few and simple parts and which is capable of qua-ntityproduction at relatively low cost.

Other and further objects will appear as the description proceeds.

I have illustrated a. preferred embodiment of my invention in the accompanying drawings in which:

Figure 1 is an elevation of the mixer as seen from the discharge side;

Figure 2 is an elevation as seen from the loading side.;

Figure 3 is an end elevation showing the mixer in tilted position;

Figure 4 is a fragmentary view on an enlarged scale showing a guide roller and drive pinion; and

the mixing drum.,

Figure 5 is a view similar to Figure 4 but showing a supporting roller.

The mixer is shown in the drawings as supported upon a trailer 1l, the details of which form no part oi the present invention. The stamlards l2 and 13 are provided with trunnon bearings adapted to receive trunnions formed upon the ends' of the cradle 14. The trunnion upon the end 15 of the cradle is formed'with an axial opening through which passes the drive shaft 1G which latter carries a gear 17 meshing with a pinion 18 upon the shaft of the motor 19. The drive shaft 16 is provided upon its other end with the pinion 2O which meshes with the rack 21 formed upon a lateral face of the guide and drive member 22 which encircles the mixing drum 23. The drum 23 is provided with the discharge opening 24 and the charging opening25.

As best shown in Figures 4 and 5, the encircling member 22 is provided with a. re-

cess 26 in the basey of which is formed the l track 27. This track 27 rests upon the two bearing rollers 28 which are carried upon stub shafts 29 fitted in lateral bosses or extensions 30 formed upon the cradle 14. The portion of the base of the lrecess other than that which comprises the track- 27 is of greater depth than the track and the. ring 22 is secured to the mixer drum 23 by rivets 39 extending into this lower portion of the recess.

As shown in Figure 4', the guide roller 31 is carried on a stub shaft 32,- the latter being adjustably secured by means of a set screw 33 in the lateral extension 41, which in the form shown are integral with the cradle 14. The stub shaft 32 is provided with the axial bore 35 through which lubricant may be conducted to the inner face of the rollers 31 which as shown are imperforate upon the side toward the base of the recess. The ball bearing 36 is fitted upon the shaft 32 and receives the roller 31, the ball bearing being held in place by disk 37 and split ring 38.

The mixer is provided with three guide rollers 31, two being carried by extensions 41 and 42, one adjacent each trunnion, and one being loc-ated upon extension 34 immediately' below the drum and between the two supporting rollers 28. The cover plate 40 extends between the lateral extensions 41 and 42 and covers the upper portion of the member 22 with its recess and rack. The tilting mechanism for the mixer comprises the hand lever 43, pivotally supported upon the 'standard 13, and the link 44 which is pivotally connected to the lower end of the lever 43 and which h-as its opposite ends pivotally connected at 45 to the cradle 14. The charging chute or hop er 50 is carried upon supports 48 and 49 w lich are secured to the. cradle 14.

In the operation of the mixer, the charge is introduced through opening 25 and the drum rotated through power supplied by the engine 19. This power is transmitted through pinion 18 to gear 17 which latter is keyed to shaft 16, the opposite end of which shaft carries the pinion 20 ymeshing with rack 21. The drum rotates, rolling upon and being supported by the spaced supporting rollers 28. These rollers engage the track 27 formed in the bottom of the recess 26. These rollers do not engage either of the lateral surfaces of the recess and are of materially less width than the recess. This makes it unnecessary to finish the remainder of the bottom of the recess through which extend the fastening rivets 3.9.

The mixing drum is maintained in fixed lateral relation to the cradle by means of the three guide rollers 31. These rollers are of slightly less diameter than the width of the recess 26. They may engage either wall of the recess but cannot engage both walls simultaneously. Their lateral clearance in the recess is small enough to prevent suicient lateral movement of the drum such as to cause the rack 2l and pinion 20 to be unmeshed, and to prevent movement in the opposite direction sutlicient to cause the gear and rack to bind. One of the rollers 31 is located immediately adjacent the pinion 20 and plav at this articular point is therefore definitely limited).

In assembling the drum with the cradle, it is placed upon the supporting rollers 28 and swung forwardly slightly until the rack 21 meshes with the pinion 20. The rollers 31 are then put in place by being positioned in the recess 26 and the shafts 32 introduced axially through the corresponding openingv in the supporting extensions 34, 41 and 42,

and Vinto the axial openings in the rollers.

The shafts 32 are next locked in place by set screws 33. The drum is then maintained in iixed relation to the cradle by means of the rollers 31 and the pinion 20.

In dumping the mixed concrete, the drum is tilted to the position shown in Figure 3 by swinging the lever 43 forwardly as seen b in Figure 1. This movement of the lever forces the link 44 and consequently the lower portion of the cradle rearwardly, and material is discharged by gravity through the opening 24. Due to the fact that the shaft 16 extends through one of the trunnions about which the mixer is tilted, the relationbetween the pinion 2O and the rack 21 remains constant during the tilting operation and the drum may be rotated while tilted,l this rotation being necessary in discharging the material.

The construction shown comprises but few parts and may be readily manufactured at comparatively small cost. The drum 'is maintained in proper relation to its drive means and to its supporting cradle. Its bearings both for support and for lateral position are upon ro 1ers which \minimizes the friction and insures operation with low expenditure of power. By means of the grooves with interfitting rollers, the number of lateral guide rollers necessary is reduced to a minimum.

While one specific form has been shown by way of illustration, I contemplate such changes as come within the scope of the appended claims.

I claim: l Y

1. In a mixing machine, a mixing drum, a. member encircling the drum having a circumferential recess therein, supporting rollers engaging the base of said recess, a single series of guide rollers fitting within and bearing against a, side wall of said recess, a circumferential rack formed exteriorly of the recess, and a drive pinion engaging said rack.

2. In a mixing machine, a mixing drum, a member encircling the drum having a circumfercntial recess therein, supporting rollers engaging the base of said recess, said rollers being of materially less width than the recess and spaced from the lateral walls thereof, and guide rollers, having a diameter slightly less than the width of the recess fitted within the recess and adapted to engage either lateral wall of the recess.

3. In a mixing machine, supports, a cradle pivoted in said supports, a mixing drum rotatably carried by said cradle, a drive member secured to the drum having a circumferential recess therein, supporting rollers engaging the base of the recess, and guide rollers bearing against a side wall of the recess, both said sets of rollers being' supported from the cradle upon members extending laterally from the plane of the cradle.

4. 'In a mixing machine, supports, a cradle pivoted in said supports, a mixing drum rotatably carried by said cradle, a drive member secured to the drum having a circumfercnt-ial recess therein, supporting rollers engaging the base of'the recess, guide rollers earing against a side wall of the recess. both said sets of rollers being supported from the cradle, an approximately radial rack 4on a laterall face of said drive. member and a pinion engaging said rack.

5. In a mixing machine, a mixing drum, a dr1ve member encircling the drum having a circumferential recess therein, a uidc roller fitted in said recess and adapteV to engage a lateral wall of the recess, a rack on an outer face of said member,

fitted upon adjacent parallel shafts.

6. In a mixing machine, a mixing drum, a. drive member encirclin the drum having a circumferential recess therein, a guide roller fitted insaid recess and adapteda to engage a lateral Wall of the recess, a rack on an outer face of said member, and a pinion engagmg said rack, the guide roller-and pinion being fitted upon adjacent parallel shafts, and the lateral clearance of the guide roller in the recess being less than the engaging depth of the gear teeth of the rack and pinion. i

7. In a mixing machine, a' mixing drum, a drive member encircling the drum having a circumferential recess therein, a guide roller fitted in said recess and adapted to engage a lateral Wall of the recess, a rack on an outer face of said member, and a pinion engaging said rack, the guide roller and pinion being fitted upon adj acen.; parallel shafts, the spacing between the shafts being such as to permit the guide roller to engage either wall of the recess while the gear and rack are maintained in operative engagement.

8. In a mixin machine, a mixing drum, a member encirc ing the drum having a circumferential recess therein, supporting roll. ers engaging the base of said recess, and a single series of guide rollels engaging a side wa l of sai'd recess, the guide and supportin rollers bein fixed relative to each other, an the guide r 1ers maintaining the supporting rollers in substantially fixed lateral relation i to the base of the recess.

In a mixing machine, a mixing drum, a drive member encircling the drum havlng a v circumferential recess therein, supporting and single series of means for the drum d by the supporting guide rollers carrie and a pinion engaging4 said rack, the guide roller and 'pinionb'eing Y.

than the recess,

v ers carried by the cradle means and adapted to bear against the lateral walls of said recess to maintain the drum in fixed lateral relation to the supporting means. t n

10. In a mixing machine, a mixing drum, a drive member enclrcling the drum having a circumferential recess therein, supportmg means for the drum, shafts carried by the supportin means and extending into the recess, an rollers carried on said shafts and adapted to bear against either of the opposite radial Walls of' the recess.

11. In a mixing machine, a mixing dr um, a drive member encirclino the drum having a circumferential recess therein, supporting means for the drum, shafts carriedby the supporting means and extending into the recess, and. rollers carried on said shafts and adapted to engage-the walls of the iecess, said roller supporting shaftsbeing adjustable axially relative tothe supporting means. 12. In a mixing machine, a mixing drum, a member encircllng the drum having a circumferential recess therein, a track formed upon the bottom of sai-d recess of less width Supporting rollers adapted to engage said track, and guide rollers adapted to bear against lateral walls of the recess to maintain the member in substantially fixed lateral relation to the supporting rollers.

A13. In a mixing machine, a mixing drum," an integral cradle supporting the drum', trunnions on said cradle, supports for said trunnions, drum guide an'd supporting rollupon integral members extending laterally from the cradle, and a member encircling the drum and provided with circumferential-recess adapted to receive the rollers.

Signed at Milwaukee, Wisconsin, this 12th day of April, 1923- ADOLPH W. RYBECK. 

